The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Air conditioning systems for vehicles normally adopt an air conditioning unit in a transverse arrangement having a cooling unit, a heating unit and an air outlet mode selecting mechanism mounted transversely in a front portion of a passenger compartment at an approximate center position in a left-right direction of the vehicle. A blower unit for blowing air to the air conditioning unit is disposed at an offset position with respect to the air conditioning unit in the left-right direction. Cool air bypassing the heating unit and warm air having passed through the heating unit are mixed together in an air mixing chamber, and the ratio between the amount of cool air and the amount of warm air is adjusted by an air mixing door to provide air at a specified temperature. A defroster opening for blowing conditioned air toward an inner surface of a windshield of a vehicle is provided at an upper side of the air conditioning unit, a foot opening for blowing air toward the feet of a passenger is provided at a lower portion of the air conditioning unit, and a face opening for blowing air toward the head of the passenger is provided at an upper side of the air conditioning unit.
The cooling unit includes an evaporator and typically all air blown by the blower unit goes through the evaporator. When the evaporator is in the cooling mode, the air blown by the blower unit is cooled and this cooling of the air can cause moisture in the air to condense on the evaporator. The condensed moisture will typically flow under the force of gravity to the lower portion of the air conditioning unit where a drain hole is provided which drains the condensed moisture to a location outside of the vehicle.
When determining the location for the drain hole in the air conditioning unit, various design considerations need to be addressed. These design considerations include, but are not limited to, the flow direction of the moisture within the air conditioning unit, the blowing air passing through the air conditioning unit, accessibility to the outside of the vehicle, and the location of other components of the vehicle in relation to the air conditioning unit.